Predicting Kentucky's Weather
How Humans and Machines Figure Out the Forecast
by: Nancy S. Grant
Shawn Harley is the guy who has to figure out what the weather will be
in eastern Kentucky. It's not easy, with winds regularly riding from the plains
and river valleys into the mountains of the 33-county area he covers. And it's
high stakes-when storms and floods are brewing, homes and lives can be on the
line.
"Due to the mountainous terrain and hilly sections here, the threat of
flooding and flash flooding is always a question," says Harley, who is Meteorologist
in Charge at the Jackson office of the National Weather Service. "On the other
hand, since this region is almost entirely forested, drought and fire dangers
are a problem in certain seasons, too."
But Harley and other Kentucky forecasters have a lot of help, from high-tech
satellites and computers linked to a national network, to the thousands of trained
weather watchers in the state's 120 counties.
The National Weather Service bases three regional offices in Kentucky,
in Jackson, Paducah, and Louisville. Those centers host the latest in computer
technology, Doppler radar, and devices to measure precipitation, wind speed, temperature,
and relative humidity. But from west to east, each of Kentucky's different land
forms and conditions offer special challenges.
Rick Shanklin, Warning Coordination Meteorologist in the Paducah NWS office,
says, "Here in the western part of the state, we tend to get more severe weather
in the winter months than the central and eastern parts of the state. We get enough
warmer weather to cause severe weather outbreaks earlier in the season and throughout
the entire year so that our average is usually a little higher than the rest of
the state."
Shanklin, like his counterparts in Louisville and Jackson, is at the center
of a vast network of local storm spotters: the Paducah office issues forecasts,
watches, and warnings for 22 counties in Kentucky and 36 additional counties in
surrounding states. The Sky Warn program Shanklin heads in the Paducah area is
typical of others in the state.
"Here, we have about 2,000 active spotters in the 58-county
area we serve," Shanklin says. "About two-thirds of them are public servants,
people such as firefighters and police, and another third are regular citizens
with a keen interest in weather and helping people." Throughout the year, each
Warning Coordination Meteorologist helps train these spotters to recognize the
difference between such things as wall clouds, funnel clouds, and tornadoes; when
weather conditions turn dangerous these spotters are ready to help.
"Our biggest challenge," Shanklin explains, "is determining if storms are
really severe or not. Our mandate from the Department of Commerce is to protect
people and property, so we rely on storm spotters to help us interpret what our
radar systems and computer models show us. We call it getting 'ground truth reports.'
"In some situations the spotters call a central dispatcher and their weather information
is then relayed to NWS personnel.
"But sometimes our spotters call us directly or we call them," Shanklin
adds. "Very often we need to ask questions back and forth to clarify what we think
is happening based on our radar and satellite images."
A trained spotter can describe the exact size of hailstones, or give eyewitness
details about wind patterns and damage to trees and structures immediately.
At the Louisville NWS office, winter weather systems present a slightly
different problem. Meteorologist Don Kirkpatrick, a lead forecaster, notes that
predicting what kind of precipitation will occur and how much can be difficult
in the lower Ohio Valley. Kirkpatrick has to make his forecasts for 49 Kentucky
counties from the Tennessee border all the way north to the Ohio River and 10
counties in southern Indiana.
"So much depends on the track of a particular storm moving in from the
plains," Kirkpatrick says. "One hundred miles either way can make the difference
between rain, freezing rain, sleet, or snow."
Another Louisville forecaster, Norm Reitmeyer, points out that not only
do NWS personnel at every office have to consider what's happening-or likely to
happen-over a large area, they must also examine columns of air extending from
the ground up to 50,000 feet into the atmosphere. All Kentucky meteorologists
analyze data gathered by NWS weather balloons launched twice a day from 70 locations
around the United States. Although none are launched from Kentucky, balloons from
Little Rock, Arkansas, Nashville, Tennessee, and Wilmington, Ohio, provide information
about wind speeds and direction, as well as air temperatures and moisture content,
when they drift over Kentucky.
At the Jackson office, which just became a full-fledged forecast office in 1996,
Harley describes what makes predictions in his area tricky: "Since we have so
many changes in elevation between large valleys and hilltops, the temperature
difference at any particular time within one county can often be 20 degrees or
more. Sometimes we can get big snowfalls on the mountaintop roads, but very little
down in the valleys."
David Stamper, Data Acquisitions Program Manager for the Jackson office,
explains that's why weather teams rely so much on the citizens in the Cooperative
Weather Observer Program. "We have people in each county who take daily measurements
of precipitation amounts and air temperature at gauges we provide." These folks
send in data regularly each day, as well as monthly reports.
Citizen volunteers in counties in extreme northeastern Kentucky provide
similar information to NWS offices in Wilmington, Ohio, and Charleston, West Virginia.
But no matter where in the state weather data is collected, it's all shared among
the NWS offices to provide the most accurate, up-to-the-minute information for
predictions and warnings. Paducah meteorologist Rick Shanklin says, "We collect
a tremendous volume of data to make a simple forecast-and we're never finished
because there's always something new developing."
Weather Watcher George Street of Henderson County
Every afternoon at five o'clock, come rain, snow, or sleet, George Street
notes whether it is raining, snowing, or sleeting. His observations go far beyond
a glance out the window. He goes to a small box in his back yard and opens it
to check weather-measuring instruments. He reads the maximum and minimum temperatures
and humidity levels for the last 24 hours; he measures precipitation; he reads
the highest and lowest soil temperatures at 4 inches and takes one reading of
the 20-inch soil temperature. After entering this information into a small hand-held
computer, he goes into his office, dials a number in Sioux Falls, South Dakota,
and plugs his computer into the phone. With this process the weather statistics
for one day in Henderson County enter the data bank of the National Weather Service.
Street is a Cooperative Observer for the National Weather Service, one
of nearly 12,000 volunteers across the nation who daily record local weather conditions.
Most volunteers record precipitation; others record precipitation and temperature;
and a few, like Street, because of experience and location, transmit more detailed
information.
Seven days a week is a major commitment, but the job has been so much a
part of Street's life for so long that he cannot remember when the weather was
not a major interest to his family.
"It's a habit now," he says. "Watching the soil temperatures rise and fall-it's
something I enjoy doing." He was a boy in 1936, but he can tell you that in July
of that year the thermometer hit 106 degrees, and he vividly remembers that 1937,
the year of the Great Ohio River Flood, was the wettest in Henderson County history.
In those years his older brother was the official observer.
"Back in the 1930s my dad wanted a chore for my brother, and he signed him up
to be a weather observer," Street says. "Then when my brother went to college,
my dad started doing it."
Street's father, Frank, kept weather records from 1940 until just before his death
in 1980, becoming over the years a highly respected authority on local conditions.
The weather hasn't changed much since the National Weather Service first
installed measuring devices on the Street farm, but the sophistication of the
instruments and the methods of reporting certainly have. When the Streets first
installed measuring devices on their farm, observers mailed in a monthly report.
Later, they talked to an agent in Louisville and, eventually, reported to an answering
machine. Today, they "plug in" to Sioux Falls.-Gail King
Weather Watcher Nettie Bowling of Clay County
Nettie Bowling of Big Creek, shown here with husband Elmer, began taking
weather observations in the 1950s in her front yard. "When it rains, I have to
note the time it starts and the time it quits, and record the amount. If it snows
I measure that, then melt it down for the liquid measurement, too. Whenever it
rains an inch or more in one hour, I have to call the Jackson office right away
and report that."-Nancy S. Grant
Weather Watcher Lorene Lewis of Harlan County
Weather observer Lorene Lewis of Big Laurel keeps daily records from a
set of gauges in her back yard, and adds, "If the water's raising in the creek
I have to call, too."-Nancy S. Grant
Want to be a weather watcher?
There are currently one or two National Weather Service Cooperative Observers
in most Kentucky counties.
"We look for people who have a fascination with weather and who are willing
to take observations seven days a week," says Deanna Lindstrom, Cooperative Program
Manager for the Paducah office of the National Weather Service. "It is a volunteer
program; that's what cooperative means-no salary."
The government provides and installs the gauges and instruments, as well
as the instrument shelter (a small box). Government weather agents also periodically
check the instruments and repair the housing. Lindstrom says that Kentuckians
who might be interested in serving as weather observers should call the nearest
NWS office. The offices in Kentucky are in Paducah at (270) 744-6440, Louisville
at (502) 969-8842, and Jackson at (606) 666-8000.-Nancy S. Grant
A Radio That Could Save Your Life
The siren you can hear tested on a clear day may not wake you up in the
middle of a stormy night. Power failures can make your TV useless. Experts agree-your
best bet during emergency weather situations is a battery-powered National Oceanic
and Atmospheric Administration Weather Radio.
In Kentucky, the National Weather Service recently upgraded its NOAA Weather
Radio broadcasting network to 30 transmitters throughout the state, capable of
sending weather information and warning signals into almost every county. But
will you know when the alarm is sounded? Only 10 to 20 percent of households nationwide
have the proper kind of radio to hear these vital warnings.
The National Weather Service wants to change that. Their goal: to make
an NOAA Weather Radio a standard part of every home, business, school, hospital,
and other public places. In any building, an NOAA Weather Radio should be as common
as a smoke detector.
NOAA Weather Radio signals operate at frequencies near 162 megahertz, too
low to be received on a typical AM/FM radio. But for about $40, you can add an
NOAA Weather Radio receiver to your emergency preparations. Some models simply
receive the basic signal and weather information; others have special features,
such as automatically turning on when alarm signals are broadcast.
Operating either on regular electricity with battery backup or completely on batteries,
the NOAA Weather Radio gives you information about dangerous situations in your
area. If you'd like to combine NOAA Weather Radio reception with other equipment,
some manufacturers are now adding the ability to receive NOAA signals to CB, scanner,
short-wave, and multi-function AM/FM radios. Check with a store clerk and read
the labels carefully when you're shopping to find the radio that will suit you.
Be prepared in every season. Make sure there's an NOAA Weather Alert Radio,
with a pack of unopened fresh batteries, wherever you work or live. The alert
tone and weather statements could save your life.-Nancy S. Grant
Weather on the Web
Get up-to-the-minute weather info and scientific details through your computer
at these Internet Web sites:
http://www.noaa.gov - National
Oceanic and Atmospheric Administration site for surface weather, plus astronomical
info such as sunspot activity
http://www.crh.noaa.gov/
- NOAA site for the central region of the U.S., with links to other sites
http://www.crh.noaa.gov/pah/
- home page of the Paducah National Weather Service office
http://www.crh.noaa.gov/lmk/
- home page of the Louisville National Weather Service office
http://www.crh.noaa.gov/jkl/
- home page of the Jackson National Weather Service office
http://wwwagwx.ca.uky.edu
- click on the Agricultural Weather Center for details such as daily soil temperature
map (note: there is no punctuation mark or space after www in this address)
www.weather.com - national
and international weather info just like what's available on TV
Energy journalist NANCY GRANT is a member of the Cooperative Communicators Association and the American Society of Journalists and Authors.
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